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# The sides of a rectangular park are in the ratio 3 : 2 and its area is 21,600 sq. mts. The cost of fencing it at Rs.2.50 per metre is

 A) Rs.1500 B) Rs. 600 C) Rs.1200 D) Rs.1800

Correct Answer:
 A) Rs.1500

Description for Correct answer:
Let the length of rectangular part be 3x

Let the breadth of the rectangular part be 2x

Area = $$\Large 3x \times 2x = 6x^{2}$$

$$\Large 6x^{2} = 21600$$

$$\Large x^{2} = 3600 => x = \sqrt{3600}=60$$

Length = $$\Large 3 \times 60$$ = 180 m.

Breadth =$$\Large 2 \times 60$$ = 120 m.

Perimeter $$\Large 2 \left(l+b\right) = 2 \left(180+120\right)$$ = 600 m.

Fencing 600m. at Rs.2.50 per metre.

=$$\Large 600 \times 2.50$$ = Rs.1500

Part of solved Area and perimeter questions and answers : >> Elementary Mathematics >> Area and perimeter

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